The present invention relates to assemblies for reinforcing materials, and more particularly assemblies intended to reinforce plastics or rubbers.
Assemblies of this general character are used to reinforce manufactured articles such as belts, tubes, plies and pneumatic tires, for example. When such assemblies are being incorporated in articles, it is important that they be entirely impregnated by a material, usually the material which they are to reinforce, and that the material penetrate into all voids in the assemblies. If penetration is incomplete, empty channels are likely to be formed along the assemblies through which corrosive agents such as water, for example, penetrating the article, perhaps as a result of cuts therein, can travel causing deterioration of the assemblies and leading to eventual deterioration of the article itself.
Various assemblies of round threads have been proposed heretofore in an attempt to secure good penetration of impregnating material into any voids between the threads. Typical assemblies of this kind are described, for example, in the patents or patent applications published under the following numbers: France Nos. 2 453 933, 2 505 372, 2,546,922, U.S. Pat. Nos. 2,900,784, 3,273,978, 4,506,500, Belgian Nos. 654 921, and 654 923. Such assemblies are either costly to manufacture because of their complexity, or are subject to incomplete penetration by the impregnating material, so that the risks of deterioration remain.
Belgian patent No. 655 591 describes a cable formed of round threads having a core surrounded by a layer formed alternately of single threads and strands. The diameter of these single threads or strands is made the same as that of the core in order better to regulate the rigidity and fatigue strength. This cable also suffers from incomplete penetration of the rubber which it is intended to reinforce and its manufacture is complicated.
Flat threads or ribbons have also been proposed for reinforcing rubber articles, such threads or ribbons being used either alone, or as core or twisted together, as described, for example, in GB Pat. No. 1 183 215, U.S. Pat. No. 3,402,546, BE Pat. No. 654 919 and FR Pat. No. 865 538. Such reinforcements are expensive to produce and/or do not afford the possibility of definitely avoiding corrosion problems due to incomplete penetration of the rubber.
It is an object of the present invention, therefore, to provide a reinforcement assembly which is economical to produce and which permits total impregnation by a material, for instance by the material which it is intended to reinforce.